Four Chicago men were ready to storm inside a home, use tape to tie up the people inside and shoot them if necessary in order to take off with more than 30 kilograms of cocaine, according to a federal complaint released Thursday. The only problem was the house allegedly filled with drugs didn’t really exist.

It was part of an investigation by the Chicago police and the FBI that included the use of undercover agents and cooperating witnesses to get suspects to reveal their own stashes of guns and drugs.

Federal and local authorities announced charges Thursday against 25 Chicago-area suspects — some alleged to be members of gangs — in a gun-trafficking investigation that resulted in the seizure of more than 60 guns.

The FBI in Chicago focused the gang investigation primarily on guns rather than drugs, said Robert Grant, special agent in charge of the Chicago office of the FBI.

In one part of the investigation, an undercover officer told a suspect the tale of a stash house he said had more than 30 kilograms of cocaine in it, according to the federal complaint. A cooperating witness had introduced the suspect, Joshua Vidal, one of the men charged, to the officer after the witness had bought guns from Vidal, according to the complaint. Vidal concocted a plan to rob the stash house and allegedly said he intended to duct-tape or even shoot the people inside to get the drugs, according to the complaint.